As known, each pole segment can be wound singularly with one or more electric conductors (in the following also referred to as wire).
As is known, the cores of dynamoelectric machines are formed of a lamination stack having slots for accommodating coils. The slots have openings for the passage of wire conductor during winding to form the coils.
In particular, the openings can be oriented towards the outside of the core component, or towards the centre of the core component.
The first case represents brushless cores wound by using rotating flyers, like is described for example in EP 1,353,435. The second case represents brushless cores wound by using a needle winder, like is described for example in EP 1,076,401.
Production lines for producing these core components usually provide a sequence of operations comprising an assembly stage of sub components on the lamination stack, a stage for winding conducting wire in the slots to form the coils, and a testing stage of the finished component core.
Each of the above mentioned operations normally requires a specific machine, which is located in a respective area of the production line. A production stage where one of the processes is carried out by one or more machines is usually considered to be a workstation of the line. For example, in the winding stage, where the winding machine is slower than machines of other stages, there can be more than one winding machine to form the workstation.
The workstations are normally positioned along a belt conveyor. The belt conveyor moves pallets carrying the core components to the various workstations.
In particular, the pallets rest on the moving belts to be transferred.
At the workstations, the core component can be removed from the pallet to be positioned inside the machine for processing. In other workstations the core components can remain on the pallet during the processing stage.
When processing requires removal from the pallet, normally a load-unload device is present for transfer of the core components between the pallet and the machine.
In particular, a first rectilinear conveyor is provided for moving pallets carrying core components to be processed at the workstations. A second conveyor, which is normally positioned adjacent to the first conveyor on a first side, returns empty pallets to the beginning of the line.
Where work stations have multiple machines, a third conveyor can be foreseen adjacent to the second side of the first conveyor. When a pallet is carrying a core component that needs to be processed by one of the multiple machines, that pallet is shifted from the first conveyor to the third conveyor in order to reach a free machine of the multiple machines, in other words a machine of the multiples machine that is not occupied processing core components. Conveyors and production lines operating according to these principles have been described in U.S. Pat. No. 4,984,353.
During conveying, the core components are recognized as being processed, or not processed, by means of information which is carried in a data block of a pallet. A data block is read along the conveyor for managing transfer of the pallet, and for requesting specific processing of the core components by the machines. Where necessary, the data block can be updated by writing devices. Reading and writing of the data blocks require stopping the pallets in alignment with the reading or writing devices.
In production lines like those of U.S. Pat. No. 4,984,353, different variations of core components are produced in a same production run. More particularly, the production line is able to output in a same production run core components that differ, for example in size of the core component, or in wire diameter. This mixed production situation requires that the production line processes simultaneously different variations of the core components according to predetermined criteria. The flow of the various variations of core components along the conveyor can become quite random, therefore the data blocks are essential for identifying the variation of the core component that is present on a pallet for specific routing through the machines of the line, which are required for processing.
It is therefore desirable to provide production lines that are improved with respect to those of the prior art that have been described in the foregoing.